Rainbow Electronics AT28HC256 - Manual

1
Features
• Fast Read Access Time – 70 ns
• Automatic Page Write Operation
– Internal Address and Data Latches for 64 Bytes
– Internal Control Timer
• Fast Write Cycle Times
– Page Write Cycle Time: 3 ms or 10 ms Maximum
– 1 to 64-byte Page Write Operation
• Low Power Dissipation
– 80 mA Active Current
– 3 mA Standby Current
• Hardware and Software Data Protection
• DATA Polling for End of Write Detection
• High Reliability CMOS Technology
– Endurance: 10 4 or 10 5 Cycles
– Data Retention: 10 Years
• Single 5V ± 10% Supply
• CMOS and TTL Compatible Inputs and Outputs
• JEDEC Approved Byte-wide Pinout
• Full Military, Commercial, and Industrial Temperature Ranges
Description
The AT28HC256 is a high-performance electrically erasable and programmable read
only memory. Its 256K of memory is organized as 32,768 words by 8 bits. Manufac-
tured with Atmel’s advanced nonvolatile CMOS technology, the AT28HC256 offers
256 (32K x 8)
High-speed
Parallel
EEPROM
AT28HC256
Rev. 0007I–12/99
Pin Configurations
Pin Name Function
A0 - A14 Addresses
CE Chip Enable
OE Output Enable
WE Write Enable
I/O0 - I/O7 Data Inputs/Outputs
NC No Connect
DC Don’t Connect
TSOP
Top View
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
OE
A11
A9
A8
A13
WE
VCC
A14
A12
A7
A6
A5
A4
A3
A10
CE
I/O7
I/O6
I/O5
I/O4
I/O3
GND
I/O2
I/O1
I/O0
A0
A1
A2
LCC, PLCC
Top View
Note: PLCC package pins 1 and
17 are DON’T CONNECT.
5
6
7
8
9
10
11
12
13
29
28
27
26
25
24
23
22
21
A6
A5
A4
A3
A2
A1
A0
NC
I/O0
A8
A9
A11
NC
OE
A10
CE
I/O7
I/O6
4 3 2 1
32 31 30
14 15 16 17 18 19 20
I/O1 I/O2 GND
DC
I/O3 I/O4 I/O5
A7 A12 A14 DC VCC WE A13
PGA
Top View
(continued)
CERDIP, PDIP, FLATPACK
Top View
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
A14
A12
A7
A6
A5
A4
A3
A2
A1
A0
I/O0
I/O1
I/O2
GND
VCC
WE
A13
A8
A9
A11
OE
A10
CE
I/O7
I/O6
I/O5
I/O4
I/O3